Joanne Krasnoff

Health‐related fitness and physical activity in patients with nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) has been referred to as the hepatic manifestation of the metabolic syndrome. There is a lower prevalence of metabolic syndrome in individuals with higher health‐related fitness (HRF) and physical activity (PA) participation. The relationship between NAFLD severity and HRF or PA is unknown. Our aim was to compare measures of HRF and PA in patients with a histological spectrum of NAFLD severity. Thirty‐seven patients with liver biopsy–confirmed NAFLD (18 women/19 men; age = 45.9 ± 12.7 years) completed assessment of cardiorespiratory fitness (CRF, VO2peak), muscle strength (quadriceps peak torque), body composition (%fat), and PA (current and historical questionnaire). Liver histology was used to classify severity by steatosis (mild, moderate, severe), fibrosis stage (stage 1 versus stage 2/3), necroinflammatory activity (NAFLD Activity Score; ≤4 NAS1 versus ≥5 NAS2) and diagnosis of NASH by Brunt criteria (NASH versus NotNASH). Analysis of variance and independent t tests were used to determine the differences among groups. Fewer than 20% of patients met recommended guidelines for PA, and 97.3% were classified at increased risk of morbidity and mortality by %fat. No differences were detected in VO2peak (x = 26.8 ± 7.4 mL/g/min) or %fat (x = 38.6 ± 8.2%) among the steatosis or fibrosis groups. Peak VO2 was significantly higher in NAS1 versus NAS2 (30.4 ± 8.2 versus 24.4 ± 5.7 mL/kg/min, P = 0.013) and NotNASH versus NASH (34.0 ± 9.5 versus 25.1 ± 5.7 mL/kg/min, P = 0.048). Conclusion: Patients with NAFLD of differing histological severity have suboptimal HRF. Lifestyle interventions to improve HRF and PA may be beneficial in reducing the associated risk factors and preventing progression of NAFLD. (HEPATOLOGY 2008.)

A randomized trial of exercise and dietary counseling after liver transplantation.

We report results of a randomized clinical trial of a combined intervention of exercise and dietary counseling (ExD) after orthotopic liver transplantation (OLT).

A randomized controlled trial of home-based exercise for cancer-related fatigue in women during and after chemotherapy with or without radiation therapy.

Background:Few studies have evaluated an individualized home-based exercise prescription during and after cancer treatment. Objective:The purpose of this study was to evaluate the effectiveness of a home-based exercise training intervention, the Pro-self Fatigue Control Program on the management of cancer-related fatigue. Interventions/Methods:Participants (N = 119) were randomized into 1 of 3 groups: group 1 received the exercise prescription throughout the study; group 2 received their exercise prescription after completing cancer treatment; and group 3 received usual care. Patients completed the Piper Fatigue Scale, General Sleep Disturbance Scale, Center for Epidemiological Studies-Depression Scale, and Worst Pain Intensity Scale. Results:All groups reported mild fatigue levels, sleep disturbance, and mild pain, but not depression. Using multilevel regression analysis, significant linear and quadratic trends were found for change in fatigue and pain (ie, scores increased, then decreased over time). No group differences were found in the changing scores over time. A significant quadratic effect for the trajectory of sleep disturbance was found, but no group differences were detected over time. No significant time or group effects were found for depression. Conclusions:Our home-based exercise intervention had no effect on fatigue or related symptoms associated with cancer treatment. The optimal timing of exercise remains to be determined. Implications for Practice:Clinicians need to be aware that some physical activity is better than none, and there is no harm in exercise as tolerated during cancer treatment. Further analysis is needed to examine the adherence to exercise. More frequent assessments of fatigue, sleep disturbance, depression, and pain may capture the effect of exercise.

Objective measures of health‐related quality of life over 24 months post‐liver transplantation

Abstract:u2002 Many studies have reported improved health‐related quality of life (HRQoL) from pre‐ to immediate post‐orthotopic liver transplantation (OLT). However, few studies have evaluated longitudinal changes over the first 2u2003yr post‐OLT and none have simultaneously examined objective measures of health‐related fitness. A total of 50 OLT recipients (32 males,18 females; 51.4u2003±u200311.8u2003yr) completed testing at 2, 6, 12, and 24u2003months post‐OLT. Testing included assessment of exercise capacity (peak VO2), quadriceps muscle strength, body composition, physical activity participation, and self‐reported functioning (SF‐36). Repeated measures of analysis of variance (ANOVA) with post hoc contrasts was performed to determine differences over time and a second ANOVA assessed differences over time between genders. All patients increased peak VO2, quadriceps muscle strength, and percent body fat (pu2003<u20030.0001) from 2 to 24u2003months. Men and women differed in their changes of peak VO2 and percent body fat (pu2003<u20030.05). At 24u2003months, only 50% of the patients reported participating in regular physical activity. All SF‐36 physical measures except general health, improved from 2 to 24u2003months (pu2003<u20030.0001). Measures of health‐related fitness and QoL improve over the first 2u2003yr post‐OLT with the greatest gains occurring in the first 6u2003months and all measures remain lower than recommended for cardiovascular and overall health. A randomized clinical trial of lifestyle modifications such as diet and exercise intervention is warranted to determine the impact of such modifications on HRQoL and fitness post‐OLT.

The Physiological Consequences of Bed Rest and Inactivity

Most dialysis patients experience prolonged periods of physical inactivity and often bedrest. The physiological consequences of bed rest and inactivity are many and detrimentally affect the functioning of many bodily systems, several of which affect physical functioning. Reductions in plasma volume reduce cardiac filling, stroke volume, and cardiac output. Skeletal muscle fiber size, diameter, and capillarity are reduced, as is bone density. These changes result in profound reductions in physical work capacity. The effects of bed rest and inactivity in patients with chronic renal failure may have more serious consequences, in that they may exacerbate the pathophysiology of renal failure such as cardiac dysfunction, anemia, muscle wasting, muscle weakness, neuropathy, glucose intolerance, and reduced bone density.

Exercise capacity and physical fitness in pediatric dialysis and kidney transplant patients

Studies of exercise capacity in children with chronic kidney disease (CKD) are limited. We tested 25 pediatric kidney transplant (TX) recipients and 15 pediatric dialysis (DX) patients. Nine children in the DX group received kidney transplants and were retested 3xa0months following surgery (pre/post). Testing involved treadmill testing with measurement of peak oxygen uptake (VO2peak), muscle strength, body composition (percent fat), and “field” tests of physical fitness using the FITNESSGRAM, which included the PACER test. Values obtained were compared with gender- and age-based criterion-referenced standards [healthy fitness zone (HFZ)]. The previous day physical activity recall (PDPAR) was used to assess physical activity participation. There were no differences between TX and DX subjects for VO2peak and muscle strength measurements, and all values were below the normative values. The TX group achieved significantly higher PACER scores, but only one TX and no DX subjects achieved the HFZ for the PACER test. No improvement in any measures were observed from pre- to post-TX in the nine subjects tested, except for a significant increase in percent fat, which negatively affected the change in muscle strength and VO2peak. All subjects were physically inactive, with less than 10% of nonschool time being physical activity participation. Pediatric patients with CKD had low exercise capacity, were physically inactive, and gained significant fat weight following TX. Counseling and encouragement for more physical activity is warranted as a part of routine medical care in these children.

The Comprehensive Assessment of Physical Fitness in Children Following Kidney and Liver Transplantation

Background. Pediatric organ transplant recipients may have elevated cardiovascular (CV) risk. Low cardiorespiratory fitness (CRF) may contribute to CV risk; however, studies of CRF in children following kidney transplantation (KTx) and liver transplantation (LTx) are limited. Methods. Laboratory testing included assessment of CRF (VO2peak), muscle strength, and body composition (%fat). Field testing (FITNESSGRAM) included the PACER, curl-up, and sit-and-reach tests. Values obtained were compared to sex- and age-based criterion-referenced standards (Healthy Fitness Zone, HFZ). The Previous Day Physical Activity Recall was used to assess after-school physical activity (PA) participation. Independent t tests were used to compare groups. Results. Twenty-five KTx and 11 LTx recipients were tested. The groups were similar in all measures. Both groups demonstrated below normative values for VO2peak and muscle strength. Only 4% of the KTx and 9% of the LTx recipients achieved the HFZ for the PACER and 24% of the KTx and 45% of the LTx attained the HFZ for the curl-up test. Approximately 44% of both groups had percent fat greater than the upper criterion value of the HFZ. Both groups reported spending only 8% of their after-school time participating in physical activity. Conclusions. Pediatric KTx and LTx recipients have significantly reduced CRF, muscle strength, and physical activity. Routine counseling and encouragement for increased physical activity is recommended as a part of routine care. A randomized clinical exercise intervention trial after pediatric solid organ transplantation is warranted to determine the impact of such lifestyle intervention on improving physical fitness and cardiovascular health.

Roles of nutrition and physical activity in musculoskeletal complications before and after liver transplantation.

End-stage liver disease (ESLD) affects thousands of people in the United States annually. Improvements in survival after liver transplantation have broadened the indications for its use as a proven therapy for ESLD, rapidly increasing the number of transplant candidates. However, the number of patients awaiting transplantation far surpasses the donor supply, resulting in lengthy waiting times. During this wait, these patients experience progressive disease-related decompensation that is often accompanied by malnutrition and reduced physical activity. This chronic disease triad can have profound effects on musculoskeletal complications, such as cachexia and osteoporosis. In the absence of proper interventional strategies before transplantation, these complications can intensify after the transplantation, as a result of continued poor nutrition intake, bed rest, and pharmacotherapies. This article discusses levels of physical functioning and nutrition status in both the pre-and post-transplant populations, the risks associated with current levels, and the roles that diet and activity therapies can have to improve outcomes.

Alterations in skeletal muscle structure are minimized with steroid withdrawal after renal transplantation.

Background. Limitations in exercise capacity in kidney transplant recipients are thought to result in part from changes in muscle structure and function associated with immunosuppression therapy. Methods. We compared the percent distribution of skeletal muscle fiber types, cross-sectional areas, and ultrastructural morphologies in kidney transplant recipients treated with standard prednisone maintenance therapy (n=21) to those undergoing rapid withdrawal of prednisone using Simulect (interleukin 2 receptor inhibitor) (n=13). Skeletal muscle biopsy specimens from the vastus lateralis were analyzed at 3 and 12 months after transplantation and compared with sedentary controls (n=15). Results. Compared with the control group, the group receiving prednisone maintenance therapy had a significantly lower percentage of type I fibers and a higher percentage of type IIB/x fibers, evident at 3 and 12 months. Fiber type distribution in patients withdrawn from prednisone did not differ from controls. In patients withdrawn from prednisone, the cross-sectional areas of type I and IIA fibers were lower and the area of type IIB/x fibers was higher compared with controls. Likewise, ultrastructural studies revealed reduced volume densities of myofibrils and higher densities of interfibrillar and subsarcolemmal mitochondria. At 12 months there were no ultrastructural differences between the patients withdrawn from prednisone and controls. Conclusions. We conclude that prednisone maintenance therapy contributes to the lower exercise capacity by altering the ratio of type I to type IIB/x fibers and by reducing myofilament density. The increase in mitochondria in patients receiving prednisone may reflect a switch from carbohydrate to lipid metabolism resulting from the glucocorticoid therapy.

Effects of Modality Change and Transplant on Peak Oxygen Uptake in Patients With Kidney Failure

BACKGROUNDnExercise capacity as measured by peak oxygen uptake (Vo₂(peak)) is low in hemodialysis patients. The present study assesses determinants of VO₂(peak) in patients with chronic kidney failure who either changed kidney replacement modality to frequent hemodialysis therapy or received a kidney transplant.nnnSTUDY DESIGNnCohort study with assessment at baseline and 6 months after modality change.nnnSETTING & PARTICIPANTSnParticipants included nondiabetic individuals receiving conventional hemodialysis who: (1) remained on conventional hemodialysis therapy (n = 13), (2) changed to short daily hemodialysis therapy (n = 10), or (3) received a transplant (n = 5) and (4) individuals who underwent a pre-emptive transplant (n = 15). Additionally, 34 healthy controls were assessed at baseline only.nnnPREDICTORnModality change.nnnMEASUREMENT & OUTCOMESnExercise capacity, assessed using the physiologic components of the Fick equation (Vo₂ = cardiac output × a-vo₂(dif), where a-vo₂(dif) is arterial to venous oxygen difference) was determined using measurement of Vo₂(peak) and cardiac output during symptom-limited exercise testing. Analysis of covariance was used to compare differences in changes in Vo₂(peak), cardiac output, heart rate, stroke volume, and a-vo₂(dif) at peak exercise between participants who remained on hemodialysis therapy and those who underwent transplant.nnnRESULTSnTransplant was the only modality change associated with a significant change in Vo₂(peak), occurring as a result of increased peak cardiac output and reflecting increased heart rate without a change in peak a-vo₂(dif) despite increased hemoglobin levels. There were no differences in participants who changed to daily hemodialysis therapy compared with those who remained on conventional hemodialysis therapy.nnnLIMITATIONSnSmall nonrandomized study.nnnCONCLUSIONSnVo₂(peak) increases significantly after kidney transplant, but not with daily hemodialysis; this improvement reflects increased peak cardiac output through increased peak heart rate. Despite statistical significance, the increase in Vo₂(peak) was not clinically significant, suggesting the need for interventions such as exercise training to increase Vo₂(peak) in all patients regardless of treatment modality.